This invention relates to a counter current decantation system for the fluid separation of liquids or solids having different densities or absorptive capacities. More particularly, this invention relates to a counter current decantation system wherein fluid separation of materials having different densities or absorptive capacities can be carried out by a means of a series of decantation pipes and pumps which cause the absorbed or lighter particles in the fluid material to be constantly pumped upstream while allowing the heavier matter to flow downwardly by gravity.
The use of counter current extraction apparatuses wherein materials having different densities or absorptive capacities are separated are well known in the art. Some of these processes operate in a vertical separator wherein the fluid passing upwardly either chemically or physically absorbs the lighter or absorptive materials and passes out of the top of the reactor as a fat solvent wherein the depleted material is removed from the bottom of the separator. These apparatuses operate on a continuous counter current flow basis and while sufficient for many operations, are not particularly useful for other separation techniques such as the chemical leaching of ores wherein repeated cycles or washings may be desirable.
On the other hand, it is shown in U.S. Pat. Nos. 3,599,791; 3,240,336; 2,631,726 that inclined counter current separators may be utilized for hydraulically sorting particulate matter of different sizes and densities. However, in these patents the force of the fluid flowing upwardly throughout the separation apparatus is a constant force adjusted such that the larger particles will flow downwardly by gravity and the upward particles will flow out the top end of the apparatus with the fluid in counter current relationship.